Electric circuit coupling



April 9, 1940. 1'. K. LAuRsEN l ELECTRIC CIRCUIIl COUPLING Fild July 13, 1938 know'.

MMLSIHO PATENT GFFICE mmc mUUl'l' @UPI-IN Lauream. Angeles, dgnorofene-foartbtohnkerllmlas andene-foubtohrthurlresn- Alleles lallllngleweolhcalif.

Amit!! 13, 1038, Serial No. 2MB

7 @In (CL 113-430) lly invention relates to an easily attachable coupling for an electric circuit, by which an electrically conducting connection may conveniently bemadetcanelectriccircuit.

Anobjectofmyinventionistoprovideacoupllng for electric circuits which is convenient and safein its operation.

Inthoseoollplinasnowincommonuaecomarising ience o a plug with two prongs and a convenutlet provided with holes for insertion of the prongs and members connecting with the whentheprongsareinstalledinthe Itis inthe also a matter of common experience that user of prong type couplings, as above described, one must orient the plug in the proper direction and exactb locate the holes in the outletbei'orctheplugcanbeinserted.andthisisa very difllcult operation to perform without visual ald.as

must be done `when the plug is to be inserted in darkness. It is an object of my invention, therefore. to provide a coupling which is easy to connect without visual aid and which can readily be connected in the dark.

Another object of the invention is to provide acouplingthatwillsupportaverticalloadwithout disconnection. This adapts my coupling to use in the combined support and electrical connection of iixtures and electrical appliances, and it is an object of my invention to provide for such use.

Still videa another object of my invention is to procoupling for electric circuits comprising members that are easily and cheaply constructed,

which are of long life, but are easily replaced.

'Diese and other apparent objects I attain in a manner that will be clear from consideration cf the following description taken in connection with the accompanying drawing, of which:

lisasectionalviewthroughawallin which the female member of my coupling is installed.

Fla. coupling Pls.

2isa'frontvlewofthememberofmy showninll'ig.l. Silasectimallviewofthememberof mycouplingshowninll'ig.2takenalongtheline 8-8 as indicated.

Fig.4isasideviewofthefemalememberof Flg.5lsanendviewofthemalememberof 5 my Couplln- Fig. 6 is a sectional view of the member shown in Fig. 5, taken along the line 8 8 as indicated.

Fig. 7 is a side view of the male member of my coupling.

Fig. 8 ls a side view of an alternative form of the male member of my coupling.

Fig. 9 is an end view of the male member of my coupling shown in Fig. 8.

Fig. 10 is a sectional view through a wall on which one form of my coupling is employed to support and electrically connect a. lamp.

My invention is illustrated as applied to a wall outlet, the wall being designated by the numeral Il. The outlet box Il is secured in the wall Il by suitable means such as screws I2 and has a. conduit i3 connected thereto through which pass the live conductors I4 and Il for supplying electric power to the outlet. The outlet box Il is preferably mounted flush with the surface of wall Il and is covered by a cover plate It secured thereto by screws I1 and provided with a hole I.. Attached to the cover plate Il within the box Il and projecting out through the hole It is the female member Il of my coupling.

The member Il comprises a body 2t preferably molded in one piece of electrical insulating material, such as synthetic resin or rubber. with molded inserts in the form of contact elements 22 and 2l to which conductors I4 and Il are c0n- 35 nected by screws 24 and 2l, respectively. The front part of member l! which projects through the plate I6 is preferablyformed with two rightangular slots 28 and 21 preferably extending in a general vertical direction and which are closed l at the bottom but open at the top and at the front face. At the front face the outer sides of the slots are preferably disposed angular-1y relative to one another so as to approach one another as they proceed from top to bottom, while the inner sides of the slots are preferably parallel to one another. The contact elements 22 and 2l are preferably ilat metal strips angularly disposed so as to be closer together at the bottom than at the top and which are bent at right angles to form contact surfaces 2l and 2| preferably lying closely along the forward walls of slots 2t and 21, respectively, approximately parsllel to the face of member Il. The outer walls ofslotsandllarcpreferablyformedbythess contact elements 22 and 25 and are angularly disposed as above described. Slots 25 and 21 are tapered from top to bottom, as seen best in Pig. 4, so that the distance between the contact surfaces 25 and 25 and the backs of the slots is less at the bottom than at the top of the slots. 'Ihe front face of body 25 is preferably cut back along a horizontal line to the backs of slots 25 and 21, as indicated at 55, and the sides of body 25 are recessed at 52 and 55 to accommodate the conductors I4 and I5, and screws 24 and 25. The screws 24 and 25 are threaded into ferminal blocks 54 and 55 which are joined, as by welding. to contact elements 22 and 25.

The male member of my coupling, designated generally by numeral 45, has a body portion 4I preferably molded in one piece of electrical insulating material such as synthetic resin material or rubber with metal inserts 42 and 45 forming contact elements extending from the body 4I in an axial direction. 'I'he contact elements 42 and 45 have joined to them, as by welding, terminal blocks 44 vand 45, respectively, and conductors 45 and 41 are connected to the terminals 44 and 45 by screws 45 and 45, respectively, which are threaded therein. The body 4I is recessed at 52 and 55 to accommodate the screws 45 and 49, and conductors 45 and 41, respectively. The contact elements 42 and 45 are preferably fiat strips of resilient metal such as bronze which are preferably although not necessarily disposed angularly relative to one another at the same angles as contact elements 22 and 25, being closer at the bottom than at the top, as seen best in Fig. 4. At their ends the contact elements 42 and 45 are preferably bent through somewhat more than a right angle to form contact flang 55 and 55 directed outwardly and slightly back toward the body of the member 45. The shape and dimensions of contact elements 42 and 45 are such that they may be inserted in the non is and 21 of member I9 and when so inserted the flanges 55 and 56 rest in spring contact with the contact surfaces 25 and 29 and with the backs of slots 25 and 21. The outer edges of flanges 55 and 55 are preferably angularly disposed relative to one another at angles corresponding to the outer walls of the slots, in engagement with which they preferably rest in the coupled relation of members and I5. The lower edges of flanges 55 and 56 are preferably rounded as at 52 to permit the easy insertion of the flanges into the slots of member I9. The body is preferably formed with an annular protuberance 51 near its forward end. Enclosing the body 4| of the member 45 is the housing 55 preferably of rubber or other resilient electrical insulating material. The housing 55 has a hole 59 at one end to permit the conductors 45 and 41 to pass through. snugly fits the exterior surface of body 4I, has an annular groove adapted to accommodate the annular protuberance 51, and projects beyond the face of body 4| a suillcient distance to result in the housing engaging the face of body 25 of member I9 when members 45 and I9 are coupled. 'Ihe housing 55 at its top and forward edge, at 5I, projects beyond the flanges 55 and 55 a sufcient distance to fill the space left at 55 in the body 25 when the members 45 and I5 are coupled, thus completely covering the connecting contact elements. 'I'he conductors 45 and 41 are attached to the contact elements before housing 55 is installed on member 45. The resilient housing 55 may then be slipped over the protuberance moans llandovertheforwarded'geofthebodyll into the position shown in the drawing.

In bringing the members of my coupling into coupled relation, the member 45 is positioned facing member I5, but above it, with the projecting portion 5I at the top. the contact elements 42 and 45areledintotheopentopsofslots 25 and21, and member 45 is forced .downward as far as it will go. In this position the angularly disposed side edges of flanges 55 and 55 preferably abut the outer walls of the slots which in this case are formed by the contact elements 22 and 25, and the member 45 lies directly opposite the member I5. Since flanges 55 and 55 engage both the contact surfaces 25 and 25, respectively. and the backs of slots 25 and 21, respectively, the flanges 55 and 55 will be deflected as they are pushed downward in the tapering slots 25 and 21 and will be forced into close resilient contact with the contact surfaces 25 and 25, thus assuring good electrical connections between the conductors I4 and I5 and conductors 45 and 41, respectively. 'I'he tightness with which the flanges 55 and 55 press against the adjacent surfaces results in a great frictional force which tends to prevent accidental removal of the member 45, and also sssures an efficient wiping and cleaning action on the contact elements during coupling and uncoupling.

It will be observed that there are several circumstances which make it easy to insert member 45 into member l5 without visual aid. The fact that the body 25 of the member I5 projects slightly from the surface of plate I5 makes it easy to locate. The presence of projecting portion 5I on member 45 makes it easy to find the top of this member. Finally, since the nanges 55 and 55 are of considerable extent and the tops of the slots are relatively wide, it is Veasy to hook these flanges into the slots in member I5 and guide the member 45 into coupled position.

It is apparent that when the members 45 and I5 are coupled no direct outward pull on the conductors 45 and 41 or on the member 45 can separate the two members but that they can only be separated by an upward pull on member 45. This is a feature of great merit which adapts my coupling to various uses not permissible with the prong type coupling.

In Figs. 8 and 9 are illustrated an alternative form of my member 45 which differs from the form shown in Figs. 5, 6, and 7 only in the shape of the contact flanges of the elements 42 and 45. In this form the contact elements 42 and 45 are preferably bent outward at right angles to form contact flanges 55 and 55 which are adapted to fit into slots 25 and 21 of member I5. In order to assure tight contact of anges 55 and 55 with contact surfaces 25 and 25, I form a transverse wave in each of the flanges 55 and 55 to result in portions 51 and 55 projecting forwardly beyond the plane of the flanges. 'Ihe lower edges of flanges 55 and 55 are preferably rounded as at 55 to permit easy insertion into the slots of member I5. It is evident that when this form of the member 45 is coupled with the member I5, the projecting portions 51 and 55 engage the backs of slots 25 and 21, respectively, and result in tight resilient contact of the anges 55 and 55 with the contact surfaces 25 and 25.

Since coupling is not disconnected by an outward pull and is capable of supporting a vertical load, I may employ it, as illustrated in Fig. l0, to support and connect an electric fixture or an electrical appliance. In Fig. 10, I show a lamp 15 inaaochet'smmortedona-tubularbracket' l`lwbichissecuredtothemalemember Il ofmy coupling. An artistic base element 18 may be attached to the combined structure toA cover the coupling and outlet box and to provide additional support against bending, and for this purpose it is preferable that the base 1I be so dimensioned astolieatagainsttbecoverplate i0 oragainst the surface of the wall I l. The conductors connecting lwith the contact elements 42 and 43 pass through the tubular bracket 'I1 and connect wtihthesocketlt. Byuseofsuchastructure as that illustrated, it is easy to install or remove a xture without connecting or disconnecting any conductors as this function is performed by the coupling; and it is not necessary to place or remove any screws or otheiI devices -for attaching the ilxture to the wall, as this function is also` rated by pulling on the cords.

It is understood that various changes'and modifications in design and construction from the embodiments disclosed herein may be made by those skilled in the art Without departing from the spirit and scope of the appended claims.

I claim as my invention:

1. An electric circuit coupling comprising: a member having two slots disposed transversely n to the axis of said coupling and on opposite sides of said axis, said slots being open at oneend and closed at the other end and extending in the same general linear direction from open to closed ends; two contact elements in said member, each of said contact elements providing a contact surface forming a wall of one oi' said slots which approaches the opposite wall as it proceeds from the open end of said slot toward the closed end thereof in such manner as to provide a wedge shape to each of said slots; a second coupling member; two contact elements extending in an axial direction from said second member and flanged transversely to provide contact flanges, said contact anges being adapted to enter the open ends of said slots and, upon bringing said members into coupledrelation, to be wedged between said contact surfaces and the opposite walls of said slots.

2. An electric circuit coupling comprising: a member having two slots disposed transversely to the axis of said coupling, said slots being open at one end; a contact element in each of said slots forming the outer and forward walls thereof, those portions of said contact elements forming said outer walls being disposed angularly relative to one another so as to lie farther apart at the openend of said slots; a second coupling member; two contact elements extending in an axial direction from said second member and carrying outwardly directed contact flanges having outer edges angularly' disposed relative to one another at substantially the same angles as said portions of said contact elements of said first member forming said outer walls of said electrically conducting cords and cables, having the advantage that the coupling cannot be sepaslots:saidcontactfiangesbeingadaptedtoeuter the open ends ofsaidslots and, whensaidmembers are in coupled relation,'to lie in said slots in contact with said contact elements of said ilrst member at both the outer and forwardy walls of said slots, in such manner that ensue-v ment of said contact ilanges with said outer walls limits the travel of said contact flanges into said slots and prevents relative rotation of said members;

3. An electric circuit coupling comprising: a member having two contact elements extending in an axial direction and flanged transversely to provide two contact flanges extending in directions opposite to one another, said contact elements providingplane surfaces angularly disposed relative w onev another; a second member having two open 4ended slots to receive said contact flanges, said slots extending in thesame general direction from their open ends and providing walls disposed at substantially the same angles as said angularly disposed plane surfaces and acting by engagement with said surfaces to limit the travel of said contact flanges into said slots and to prevent relative rotation of said members; and contact elements in said slots adapted to contact with said contact flanges in the coupled relation of said members.

4. An electric circuit coupling comprising: a member having two slots disposed transversely to the axis of said coupling and in communication with the face of said member, said slots being open at one end and closed at the other end and extending in the same general direction from open to closed ends; a contact element in each of said slots providing a contact surface forming a Wall of said slots which approaches the opposite wall as it proceeds from the open end of said slot toward the closed end thereof; a second coupling member adapted, when said members are in coupled relation, to lie adjacent said face of said i'lrst member; and two contact elements extending from said second member and iianged transversely to provide contact flanges, said contact elements of said second member providing surfaces angularly disposed relative to one another; said contact iianges being adapted, when said members are in coupled relation, to lie in said slots wedged between said contact surfaces and the opposite walls of said slots; said slots providing walls disposed at substantially the same angles as said angularly disposed surfaces and acting by engagement with said angularly disposed surfaces to limit the travel of said contact anges into said slots and to prevent relative rotation of said members.

5. An electric circuit coupling comprising: a member having two slots disposed transversely to the axis of said coupling on opposite sides of said axis and in communication with the face of said member, said slots being open at one y end and closed at the other end and extending adapted, when said members are in coupled relation, to lie in one of said slots and each being deformed in an axial direction into such a shape that in bringing said members into coupled relation a portion of each of said contact anges engages the contact surface in its respective slot and another portion of said contact iiange engages the opposite wallof said slot and said contact flanges are detlectedby reason of said engagement and are thereby held in resilient contact with said contact surfaces.

6. An electric circuit coupling comprising: a member adapted to be mounted in a. Wall and having two slots therein, said slots being disposed in a general vertical direction and being open at the top; a contact element in each oi' said slots providing a contact surface forming a wall of said slot `which approaches the opposite wall as it proceeds from top to bottom; a second coupling member adapted, when said members are in coupled relation, to lie adjacent to the face of said first member; two contact elements of resilient metal extending from said second member and flanged transversely to provide contact iianges, said Contact elements of said second member providing plane surfaces angularly disposed relative to one another; each of said contact ilanges being adapted, when said members are in coupled relation, to lie in one of said slots and each being so shaped as to have a portion engaging the contact surface within said slot and another portion engaging the opposite wall of said slot, whereby said contact flanges are deected by reason of said engagement and are thereby held in resilient contact with said contact surfaces; said slots providing walls acting by engagement with said angularly disposed surfaces to limit the travel of said contact flanges into said slots and thereby support said second member non-rotatably on said nrst member. in the coupled relation of said members.

7. An electric circuit coupling comprising: a

' member having two ilat strips extending in an axial direction and flanged transversely to provide contact anges, said strips being disposed at an angle relative to one another so as to lie closer to one another at the bottom than at the top; a second member having two slots open at their tops to receive said contact flanges, said slots extending in the same general direction from their open ends and providing side walls disposed at substantially the same angles as said strips so as to lie closer to one another at the bottom than at the top, said walls being adapted to engage the outer sides of said strips to limit the travel of said contact iianges into said slots in the operative relation of said members; and contact elements in said slots adapted to contact with said contact flanges in the operative relation of said members.

THORVALD K. LAURSEN. 

